<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      .box {
        width: 500px;
        height: 500px;
        background-color: pink;
        margin: 20px;
        position: relative;
      }
      .one {
        width: 100px;
        height: 100px;
        background-color: skyblue;
      }
      .two {
        width: 100px;
        height: 100px;
        background-color: yellow;
        position: absolute;
        top: 0;
      }
    </style>
  </head>
  <body>
    <div class="box">
      <div class="one">我是盒子1</div>
      <div class="two">我是盒子2</div>
    </div>
  </body>
</html>
